Type::Tiny::Union(3) User Contributed Perl Documentation Type::Tiny::Union(3)

# [NAME](#NAME)

Type::Tiny::Union - union type constraints

# [SYNOPSIS](#SYNOPSIS)

Using via the "|" operator overload:

```
  package Local::Stash {
    use Moo;
    use Types::Common qw( ArrayRef HashRef );
    
    has data => (
      is   => 'ro',
      isa  => HashRef | ArrayRef,
    );
  }
  
  my $x = Local::Stash->new( data => {} );  # ok
  my $y = Local::Stash->new( data => [] );  # ok
```

Using Type::Tiny::Union's object-oriented interface:

```
  package Local::Stash {
    use Moo;
    use Types::Common qw( ArrayRef HashRef );
    use Type::Tiny::Union;
    
    my $AnyData = Type::Tiny::Union->new(
      name             => 'AnyData',
      type_constraints => [ HashRef, ArrayRef ],
    );
    
    has data => (
      is   => 'ro',
      isa  => $AnyData,
    );
  }
```

Using Type::Utils's functional interface:

```
  package Local::Stash {
    use Moo;
    use Types::Common qw( ArrayRef HashRef );
    use Type::Utils;
    
    my $AnyData = union AnyData => [ HashRef, ArrayRef ];
    
    has data => (
      is   => 'ro',
      isa  => $AnyData,
    );
  }
```

# [STATUS](#STATUS)

This module is covered by the Type-Tiny stability policy.

# [DESCRIPTION](#DESCRIPTION)

Union type constraints.

This package inherits from Type::Tiny; see that for most documentation. Major differences are listed below:

## [Constructor](#Constructor)

The "new" constructor from Type::Tiny still works, of course. But there is also:

[new\_by\_overload(%attributes)](#new_by_overload%28_attributes%29)

Like the "new" constructor, but will sometimes return another type constraint which is not strictly an instance of Type::Tiny::Union, but still encapsulates the same meaning. This constructor is used by Type::Tiny's overloading of the "|" operator.

## [Attributes](#Attributes)

"type\_constraints"

Arrayref of type constraints.

When passed to the constructor, if any of the type constraints in the union is itself a union type constraint, this is "exploded" into the new union.

"constraint"

Unlike Type::Tiny, you *cannot* pass a constraint coderef to the constructor. Instead rely on the default.

"inlined"

Unlike Type::Tiny, you *cannot* pass an inlining coderef to the constructor. Instead rely on the default.

"parent"

Unlike Type::Tiny, you *cannot* pass an inlining coderef to the constructor. A parent will instead be automatically calculated.

"coercion"

You probably do not pass this to the constructor. (It's not currently disallowed, as there may be a use for it that I haven't thought of.)

The auto-generated default will be a Type::Coercion::Union object.

## [Methods](#Methods)

[find\_type\_for($value)](#find_type_for%28$value%29)

Returns the first individual type constraint in the union which $value passes.

[stringifies\_to($constraint)](#stringifies_to%28$constraint%29)

See Type::Tiny::ConstrainedObject.

[numifies\_to($constraint)](#numifies_to%28$constraint%29)

See Type::Tiny::ConstrainedObject.

"with\_attribute\_values($attr1 => $constraint1, ...)"

See Type::Tiny::ConstrainedObject.

## [Overloading](#Overloading)

•

Arrayrefification calls "type\_constraints".

# [BUGS](#BUGS)

Please report any bugs to <https://github.com/tobyink/p5-type-tiny/issues>.

# [SEE ALSO](#SEE_ALSO)

Type::Tiny::Manual.

Type::Tiny.

# [AUTHOR](#AUTHOR)

Toby Inkster <tobyink@cpan.org>.

# [COPYRIGHT AND LICENCE](#COPYRIGHT_AND_LICENCE)

This software is copyright (c) 2013-2014, 2017-2025 by Toby Inkster.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

# [DISCLAIMER OF WARRANTIES](#DISCLAIMER_OF_WARRANTIES)

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

2026-06-28 perl v5.42.2

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Document: Type::Tiny::Union(3pm) from perl-type-tiny 2.010001-r3 (Chainguard OS)
Source: https://github.com/tobyink/p5-type-tiny